lisa.tests.base: Add ResultBundle.context
lisa.tests.base: Add ResultBundle.context

ResultBundle.context attribute is a dictionary of contextual information, such
as board name or kernel version. It can be seen as a light subset of
PlatformInfo, which is not possible to store in ResultBundle to preserve
efficient serialized storage (PlatformInfo is too big).

credp/lisa,ARM-software/lisa,ARM-software/lisa,ARM-software/lisa,credp/lisa,credp/lisa,ARM-software/lisa,credp/lisa